Iron regulatory protein 1 is required for the propagation of inflammation in inflammatory bowel disease.

Inflammatory bowel diseases (IBDs) are complex disorders. Iron accumulates in the inflamed tissue of IBD patients, yet neither a mechanism for the accumulation nor its implication on the course of inflammation is known. We hypothesized that the inflammation modifies iron homeostasis, affects tissue iron distribution, and that this in turn perpetuates the inflammation.

Reply to the Comment on "Revisiting the carrageenan controversy: do we really understand the digestive fate and safety of carrageenan in our foods?" by M. Weiner and J. McKim, Food Funct., 2019, 10: DOI: 10.1039/C8FO01282B.

This commentary re-emphasizes the aim of our recent review (David et al., 2018) and addresses some of the points raised in the adjacent commentary by M. Weiner and J.

Revisiting the carrageenan controversy: do we really understand the digestive fate and safety of carrageenan in our foods?

Carrageenan (CGN), a family of marine polysaccharides isolated from seaweeds, has been at the heart of considerable debate in recent years. To date, CGN is generally recognized as safe based on a history of safe use, various acute toxicology studies and some recent chronic toxicology tests. This review offers readers an overview of evidence on CGN characteristics and digestive fate that highlight various gaps in our understanding.

Digestive fate of dietary carrageenan: Evidence of interference with digestive proteolysis and disruption of gut epithelial function.

Scope: The objective of this study was to interrogate two mechanisms by which commercial Carrageenans (E407) (CGN) may adversely affect human health: (i) Through modification of gastric proteolysis and (ii) Through affecting gut epithelial structure and function.

Methods And Results: Three commercial CGN samples with distinct zeta-potentials (stable at the pH range of 3-7 and varied with physiological levels of CaCl ) were mixed with milk, soy or egg protein isolates, then subjected to a semi-dynamic in vitro digestion model and analyzed by SDS-PAGE. This revealed varying levels of interference with gastric digestive proteolysis and a significant decrease in pepsin activity.

Corrigendum: Ferritin polarization and iron transport across monolayer epithelial barriers in mammals.

[This corrects the article on p. 194 in vol. 5, PMID: 25202274.

Ferritin polarization and iron transport across monolayer epithelial barriers in mammals.

Epithelial barriers are found in many tissues such as the intestine, kidney and brain where they separate the external environment from the body or a specific compartment from its periphery. Due to the tight junctions that connect epithelial barrier-cells (EBCs), the transport of compounds takes place nearly exclusively across the apical or basolateral membrane, the cell-body and the opposite membrane of the polarized EBC, and is regulated on numerous levels including barrier-specific adapted trafficking-machineries. Iron is an essential element but toxic at excess.